4-Hydrazinylbenzenesulfonamide hydrochloride → HCID 22315385, compound

Participants

Reaction Steps

A 500 mL one neck round bottomed flask equipped with reflux condenser, nitrogen inlet and provisions for magnetic stirring was charged with 3,4-dihydro-6-methoxy-2-[2,2-difluoro-1-hydroxyethylidene]-1(2H)-naphthalenone from Step 1 (2.54 g, 10 mmol), 4-sulfonamidophenylhydrazine hydrochloride (2.91 g, 13 mmol) and 250 mL of absolute ethanol. The solution was warmed to reflux for 15 hours and concentrated in vacuo. The residue was dissolved in ethyl acetate, washed with water and with brine, dried over anhydrous MgSO4, filtered and reconcentrated in vacuo. The residue was recrystallized from a mixture of ethanol and water to give 4-[3-(difluoromethyl)-4,5-dihydro-7-methoxy-1H-benz[g]indazol-1-yl]benzenesulfonamide (3.3 g, 82%): mp 256°-257° C.

Provenance & Evidence